LOCATION GRACOT COEstablished Series
TAXONOMIC CLASS: Sandy, mixed, frigid Ustic Torriorthents
TYPICAL PEDON: Gracot very gravelly loamy sand - rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 5 inches; brown (10YR 5/3) very gravelly loamy sand, brown (10YR 4/3) moist; single grain; loose, nonsticky and nonplastic; 45 percent pebbles; 15 percent cobbles; strongly effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (3 to 6 inches thick)
C--5 to 16 inches; pale brown (10YR 6/3) extremely gravelly loamy sand; dark yellowish brown (10YR 4/4) moist; single grain; loose, nonsticky and nonplastic; 60 percent pebbles, 15 percent cobbles; strongly effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (9 to 25 inches thick)
2C--16 to 60 inches; light gray (10YR 7/2) fine sand, grayish brown (10YR 5/2) moist; single grain; loose, nonsticky and nonplastic; strongly effervescent; mildly alkaline (pH 7.8).
TYPE LOCATION: Moffat County, Colorado; about 8 miles south of Maybell, Colorado; about 2,600 feet east and 1,800 feet north of the southwest corner of Sec. 5, T. 5 N., R. 95 W. Longitude: 108 degrees, 5 minutes, 3 seconds west. Latitude: 40 degrees, 24 minutes, 38 seconds north.
RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 44 to 46 degrees F. The moisture control section is moist in some or all parts for 30 consecutive days immediately following May 1. It is dry in all parts for 45 consecutive days immediately following July 1. The soil is usually calcareous to the surface, but may be noncalcareous in the upper few inches in some pedons. Depth to the 2C horizon is 15 to 30 inches. The particle- size control section averages 15 to 35 percent rock fragments.
The A horizon has hue of 2.5Y or 10YR, value of 4 or 5 dry, 3 or 4 moist, and chroma of 2 or 3. Reaction is mildly alkaline or moderately alkaline.
The C horizon has hue of 2.5Y or 10YR, value of 5 or 6 dry, 4 or 5 moist, and chroma of 2 through 4. It is extremely gravelly loamy sand, very gravelly loamy sand, extremely gravelly sand, or very gravelly sand. Content of rock fragments is 45 to 75 percent. Reaction is mildly or moderately alkaline.
The 2C horizon has hue of 2.5Y or 10YR, value of 6 or 7 dry, 5 or 6 moist, and chroma of 2 or 3. It is fine sand or sand. Reaction is mildly alkaline or moderately alkaline. Content of rock fragments ranges from 0 to 5 percent.
COMPETING SERIES: These are the Dayschool(T)(MT) and Vible (T)(WY) series. Dayschool soils have 10 percent or less rock fragments in the particle-size control section above 40 inches. Vible soils are noncalcareous.
GEOGRAPHIC SETTING: Gracot soils are on hills and breaks. Slopes range from 5 to 30 percent. The soil formed in residuum derived from sandstone capped with alluvial gravel. Elevation ranges from 6,000 to 6,800 feet. The mean annual precipitation ranges from 11 to 13 inches. Mean annual temperature ranges from 42 to 45 degrees F. The frost-free period is about 75 to 95 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Coyet, Maybell, Rock River, and Ryan Park series. All these soils lack skeletal horizons within the particle-size control section. In addition, Rock River and Ryan Park soils are not in the sandy family and have argillic horizons.
DRAINAGE AND PERMEABILITY: Excessively drained; slow runoff; rapid permeability.
USE AND VEGETATION: These soils are used for rangeland and wildlife habitat. Native vegetation consists of Indian ricegrass, western wheatgrass, prairie junegrass, needleandthread, antelope bitterbrush, and black sagebrush.
DISTRIBUTION AND EXTENT: Gracot soils occur in northwestern Colorado. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Moffat County (Moffat County Area), Colorado, 1991.
REMARKS: Diagnostic horizon recognized in this pedon is the ochric epipedon - the zone from 0 to 5 inches. Last updated by the state 12/90.